The Histopathology and Microbiology Core (Core B) is dedicated to serving Projects 1-4 of this Program Project Grant in regard to analysis of human and animal samples. This core will ensure the quality control of sample analysis and testing throughout the Program Project Grant. The specific objectives of Core B are: 1. Evaluation of general (non-neurogenic) airway inflammation in human airway and/or mouse lung samples 2. Evaluation of neurogenic inflammation in human airway and/or mouse lung samples 3. Evaluation of airway remodeling in human airway and/or mouse lung samples 4. Quantitative M. pneumoniae culture and PCR in human airway and mouse lung samples 5. Measurement of serum IgE and IgG levels in murine models 6. Transmission electron microscopy of M. pneumoniae treated with surfactant protein-A (SP-A) Thus, Core B will be an integral part of the Program Project Grant and in doing so will have the projects function at a high standard.